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    2LB system for Tankless Water Heater And Fireplace (9 Posts)

  • barmesome1955 barmesome1955 @ 4:43 AM
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    2LB system for Tankless Water Heater And Fireplace

    Hello Everyone, I am in the process of taking my electric water heater out and replacing it with a Rinnai heater. The gas company has already ran the gas line from the street to the house and it is going to be a 2lb system. I have ran 3/4 black pipe off of the heater with a union and cut off and dip leg in the line before going through the brick wall with a sleeve. I put a tee in the 3/4 line to run a small fireplace line off of later. I called the gas company to see how much they would charge to run the fireplace line and they sent a guy out here. He looked at my work and said it looked real good but he would have to take all the black pipe out and start over again and I ask why and he said I could not run the 199,000 btu tankless heater and the fireplace off of the 3/4 black pipe I put in. I have not done this in 15 years and I don't understand why my piping is not right. The fireplace is 40ft away from my and the line has to be run in the atic, I am on a slab. The price to do this was 1,050.00, I told them to get the he@# out of my yard that is how mad I got. I am trying to save money by going with gas but it will take 50 years to start saving any money. I am going to try and send a photo of what I have done so maybe someone can lead me in the right direction. Thanks everyboby!!!
    I love to fix things myself, just to see if I can.
  • Zman Zman @ 9:02 AM
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    2 #

    2 # is not a normal pressure for residential appliances.1/4# or 7" water column is the norm.
    Gas piping is sized by adding up the total length of the fittings and calculating the pressure drop. If you are going to do this yourself, you need to get a handle on this. It is really important. Get the BTU rating of the appliances and start working. As for what you have installed, The drip leg should be on each appliance not the main. Strapping the pipe is very important.
    Carl
  • barmesome1955 barmesome1955 @ 2:15 PM
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    2LB system for Tankless Water Heater And Fireplace

    Thak's for the reply Carl
    I live in Winston Salem NC and I thought the gas company would put the regulator by the meter when they set it. (this Is My House I am Working On) I have not got this system inspected yet ,just got a permit to do it. I wanted to make sure I am putting in the right size pipe and to make sure I did not need to change anything before I called for final inspection. The meter is right outside the wall where the 3/4 line is running out. It is right behind the W/H on the outside wall. No more than 10 ft of 3/4 pipe. Should I go ahead and take this piping out and start over and put a regulator in myself under the union at the bottom of the W/H? Will 3/4 not run my W/H and Gas log on a 2lb system. I am thinking of not even hoking up my gas logs because it is so close to spring time. Thanks
    I love to fix things myself, just to see if I can.
  • barmesome1955 barmesome1955 @ 12:00 PM
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    posted twice, sorry

    I love to fix things myself, just to see if I can.
    This post was edited by an admin on February 13, 2013 2:19 PM.
  • Zman Zman @ 11:44 PM
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    2 #

    I am still trying to figure out this 2# thing. Your rinnai will not run on 2#. A 2# fireplace is unusual. This chart may help with the sizing http://www.engineeringtoolbox.com/natural-gas-pipe-sizing-d_826.html
    Carl
  • barmesome1955 barmesome1955 @ 6:05 AM
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    2LB system for Tankless Water Heater And Fireplace

    Thank's for the replies everyone, I am going to hire someone that know's what they are doing! I don't want to have a big big boom!!!
    I love to fix things myself, just to see if I can.
  • Bob Harper Bob Harper @ 11:40 PM
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    2lb for tankless and Fp

    You need to run the calculations. Do the Longest Run Method. At the very least, I would increase the pipe in from the meter to the tankless to 1" min. Since it is a short run, why not go bigger? You see, these things can draw so much gas so fast, they can drop out a standing pilot on fireplaces.

    As for the piping shown, it is wrong. You can put a trap there but it is supposed to be close to the appliance. The biggest problem is the shutoff. It kills both appliances. You should relocate it to control the tankless only. You can put another shutoff on the leg to the fireplace right there in that room but you'll need one at the fireplace within 6 ft. under many codes. The IRC does allow the shutoff for a fireplace to be remote of the fireplace under three conditions: it controls only the Fp, it is labeled such and it is "readily accessible".

    You are allowed to run 2 psi into the house then place a Medium Pressure regulator there, usually upstream of a manifold. You would need a shutoff then sediment trap, regulator, then another tee or means to tap for an outlet pressure. As stated, the inlet pressure to the appliances is on the rating plates but generally around 5-7 wci for NG and 10.5-11wci for LP with 14 wci/ 1/2psi max.

    HTH
  • pipeking pipeking @ 10:47 AM
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    what makes u

    think that u have 2psi of gas in your house? that sounds like the street pressure.
  • barmesome1955 barmesome1955 @ 9:09 PM
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    Tankless Water Heater

    2lb is what the gas company said the meter would be, I am thinking the plumber will have to put regulators on my tankless w/h and fireplace to go from 2lb to inches. don't think I am going to do the gas piping myself anyways, It is to dangerous if It is not done right. Thanks for all the replies. I had rather be safe than sorry.
    I love to fix things myself, just to see if I can.
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